Accuracy/Velocity Info

[Shadow 4]

Hi,

New here, but I see a lot of familar names.

Been reloading for 30 yrs and shooting the Sharps for 22 years. I don't shoot the matches much, mostly time/$$ issues and the fact that I have a personal range that gets me shooting almost every day. I only have targets to 880yards, but have run the 50BMG out of gas on the property. (4000yrds+/-)

I reciently started to really work on Blackpowder use at long(er) ranges..

I have a few questions, and I would sure apprciate some advise...

I have a pilots certificate and learned through aeronautics that if you double (2x) the velocity you will quadruple (4x) your drag. With this info, I question the idea of extra velocity being helpful at longer ranges with the Sharps... But....

My recent load is: 45-70, 74 sharps 1/18twist
61gr Swiss 1 1/2
24" drop tube
535 Gr Lyman Postell
210Fed Primer
Win Case, fire formed, slight neck size
.95 gasket wad+Newsprint
Hand seated bullet, No compression.

With with this load in my 45-70, I just shot a 6 shot group at 300 yards that measured 2.25". It (was actually 9 shots but the first was clean barrel, the 2nd gave me a sight change and I pulled one terrible...which left me 6 clean shots into a nice 2 1/4" circle@300yds off the bench)

This same load seems to really fall apart at 680yrds...I can keep all shots on a 20" circle but no group seems to form??

My ???'s

Will extra velocity help with stablizing at the extended ranges? Or will the (extra) drag issues slow the fast bullet so fast that the 1100fps load is about the same velocity as the 1250fps load when they reach 700+yards?? Is it worth it for the extra fps at the muzzle?

The other ? is:
Sound Barrier (mach)...I know that this can cause severe turbulence when it is broken and when the bullet slows back through it...Is is better to get below Mach sooner or later???

Thanks for any help!! Please feel free to question or add infomation to this as it would sure help me out.

Freedom!

I've got my 535 gr money bullet running at 1250fps+- it seems to work well to 1200 yrds. They gotta get to speed and be stable from the start or they never will be much good